usb: host: xhci: Remove some unnecessary return value initializations

The ret/retval will be set when it used, no need to init at definition.

[modified subject line -Mathias]

Signed-off-by: Linyu Yuan <quic_linyyuan@quicinc.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20220303110903.1662404-10-mathias.nyman@linux.intel.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>